Magnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting and processes in the mantle wedge

  title={Magnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting and processes in the mantle wedge},
  author={Gene M Yogodzinski and Robert W. Kay and Oleg N. Volynets and A. V. Koloskov and Suzanne Kay},
  journal={Geological Society of America Bulletin},
The role of the subducting lithospheric slab in the genesis of mantle-derived (primitive) magmas is investigated through a study of volcanic rocks formed in the tectonically strike-slip–dominated western Aleutian arc. Two types of chemically and petrologically distinctive primitive andesites have been found among the Miocene–late Pleistocene–age volcanic rocks in the western Aleutians. These are termed the “Adak-type” and “Piip-type” magnesian andesites. Trace element and isotopic… Expand
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High-magnesian andesites of middle Miocene age occur in southwest Japan, forming an obvious volcanic belt. These andesites have low FeO*/MgO ratios (0.546–0.931), and are rich in Ni (101–312 ppm), CoExpand
Volcanic Arc Magmas: Implications of a Melting-Mixing Model for Element Recycling in the Crust-Upper Mantle System
  • R. Kay
  • Geology
  • The Journal of Geology
  • 1980
A multicomponent melting-mixing model for the origin of volcanic arc basalt magmas implies signifi cant recycling of K, Rb, Ba, and other elements in the crust-upper mantel system. The model accountsExpand
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In the mid-late Tertiary (27–6 m.y. ago), volcanism diminished, then ceased in the main Andean Cordillera in Chile between 29° and 30°30′S. Over the same time span the subduction angle shallowedExpand
Chemical characteristics of fluid phase released from a subducted lithosphere and origin of arc magmas: Evidence from high-pressure experiments and natural rocks
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Slab-mantle interactions
Abstract Intraplate magmas worldwide display a set of geochemical and isotopic characteristics which seem to have been produced by a common petrogenetic process connected with the subduction ofExpand